Question

Срочно! Очень прошу!!!

Answer 1

1) (x³-y³)/(x-y)):(x²-y²)=(x³-y³)/((x-y)(x²-y²))=(x-y)(x²+xy+y²)/((x-y)(x²-y²)=
=(x²+xy+y²)/(x²-y²).
2. (x²+xy+y²)/(x²-y²)+xy/(x²-y²)=(x²+xy+y²+xy)/(x²-y²)=(x²+2xy+y²)/(x²-y²).
3) (x²+2xy+y²)/(x²-y²)-2x/(x-y)=(x²+2xy+y²-2x*(x+y))/(x²-y²)=
=(x²+2xy+y²-2x²-2xy)/(x²-y²)=(-x²+y²)/(x²-y²)=-(x²-y²)/(x²-y²)=-1.